This invention pertains to electrical grounding systems, including metallic and/or antenna support cable structures, ground planes, and brackets. More particularly, this invention relates to an electrical grounding bracket, otherwise referred to as a ground bar or earth bar, that is attached to a support structure such as a mast antenna or a ladder ground kit or is used as a connection device in order to ground cables or wires to any metallic or electrically conductive bracket and/or support structure.
Mounting systems for grounding electrical system connectors and components have been known in the art in order to mitigate possible damaging effects resulting from electrostatic discharge or lightning and mitigate possible damaging effects and/or electrical noise resulting from electrical discharge or lightning. For example, grounding clamps have been used to ground coaxial cable junction boxes to tubular grounding members, such as an electrical service conduit. Numerous other grounding clamps are known in the art.
One particular application requiring improvements is the mounting and grounding of wireless telecommunications antenna system components. Typical antenna installations are generally crowded due to the limited availability of towers and antenna masts upon which such antennas are mounted. For example, the availability of antenna sites has recently been restricted due to zoning laws and limited availability of antenna tower locations which has crowded existing towers with a large number of antennas and associated antenna system components. One particular problem resulting from antenna tower crowding is the limited space available to ground and support electrical cables and components that are associated with an antenna tower. In one case, there exists a need for a ground bar that can be mounted to both c-profiles and cable ladders for grounding and supporting wireless communication networks and/or systems which include, but are not limited to, Groupe Speciale Mobile (GSM) and microwave (MW) cable and antenna system components.
For example, as seen in the prior art apparatus depicted in FIG. 2, a signal carrying cable is supported and grounded using a ground bar 34 mounted along a c-profile 31 that is typically provided at the base of an antenna mast. However, such ground bar 34 is supported at opposite ends in a manner that is axially aligned atop c-profile 31 which necessitates placement of bar 34 directly on top of c-profile 31. Such placement takes a considerable amount of space atop c-profile 31, thereby reducing the overall space available along c-profile 31.
As shown in FIG. 2, ground bar 34 includes a plurality of apertures 36 sized for receiving fasteners that connect with ground wires of an antenna electrical system. Accordingly, a total of ten different ground wires can be connected to ground bar 34, thereby grounding such ground wires onto c-profile 31. Additionally, end slots 38 are provided at each end of ground bar 34. Each fastener 40 cooperates with a retaining washer 42 and a lock washer 44 via a nut (not shown) wherein washer 42 and bar 34 cooperate in fastened assembly to capture bar 3411 about the open slot of c-profile 31.
However, ground bar 34 takes up a relatively large footprint on a c-profile, thereby significantly reducing the available room for securing additional ground bars or other components. Additionally, ground bar 34 is sized only for mounting on one specific size of c-profile. Furthermore, ground bar 34 cannot be easily or efficiently mounted onto cable ladders.
Furthermore, for cases where there is limited mounting space (i.e., availability of c-profiles), there exists a need for a mounting structure that takes up less space than ground bar 34 along a mounting structure. Furthermore, there exists a need for a ground bar that is capable of being mounted in several different configurations on several different types of electrically conductive support structures of an antenna system. Such a ground bar will reduce the need for several different types of ground bar designs and/or mounting brackets.
An electrical ground assembly, or grounding device, is provided for mounting and grounding electrical components of a communication device to a support structure such as an antenna tower or a ladder and/or rail structure associated with an antenna tower or other support structure. Hardware dead ends and junction points are grounded to mitigate electrical noise, to protect personnel, to provide electrical grounding protection, and to provide lightning surge protection. Typically, multiple grounds are provided along components and cable shields of a communication device. The grounding device is versatile and adaptable to facilitate mounting to a support structure in a variety of mounting configurations, and while reducing the amount of mounting space needed for securement to the support structure. Furthermore, two different embodiments are provided in order to accommodate grounding of varying amounts of electrical components to a single grounding device.
According to one aspect, an electrical component grounding device includes a ground bar, a fastener, and an elongate backing plate. The ground bar includes an elongate electrical contact bridge having at least one electrical contact, a retainer bracket angularly depending centrally of the bridge, and a fastener receiver. The fastener communicates with the ground bar via the fastener receiver. The elongate backing plate has a fastener receiver mating with the fastener and operative to engage together the ground bar and the backing plate about a support structure. The backing plate and the fastener further cooperate to support the backing plate for rotatable positioning relative to the ground bar to facilitate assembly of the grounding device to the support structure.
According to another aspect, an electrical system grounding and support apparatus includes an electrically conductive grounding bracket and a fastener. The electrically conductive grounding bracket includes an elongate cross-member having a plurality of electrical contacts for receiving ground wires and a mounting tab depending from the cross-member. The fastener cooperates with the grounding bracket to secure the grounding bracket in an electrically conductive relation with a ground support structure. The tab cooperates in assembly with the support structure to resist rotation of the grounding bracket on the support structure.
According to yet another aspect, an antenna component grounding system includes a ground bar and a retainer plate. The ground bar has an elongate electrical contact portion for providing electrical contact for an antenna component and a mounting portion depending from the electrical contact portion for retaining the ground bar to an electrically conductive support structure. The retainer plate is carried by the ground bar. The ground bar and the retainer plate cooperate to capture a support structure therebetween such that the support structure carries the grounding system.